SOLID-STATE-QUIZ-10

Solid State Quiz-10

Dear Readers,

The one subject in NEET which is candidates who can easily attain good marks is Chemistry. That's the reason, often, one doesn’t pay notice and choose to compromise it. But if one wants to rank above others, the tip is to be thorough with NEET chemistry concepts. The understanding of reactions and definite basic understanding is what requires major attention in Chemistry but once done it only gets simpler from there. The main focus on the to-do list should be on getting a hang of the NCERT syllabus of NEET chemistry..

Q1. The yellow colour of ZnO and conducting nature produced in heating is due to:

•  Metal excess defects due to interstitial cation
•  Extra positive ions present in an interstitial site
•  Trapped electrons
•  All of the above

Solution
These are characteristics of metal excess defects due to interstitial cation.

Q2.Which is ferromagnetic?

•  Ni
•  Co
•  
•  All of these
  

Solution
Ferromagnetics are the substances which are strongly attracted in magnetic field and retain magnetism in absence of magnetic field.

Q3.  Which arrangement of electrons leads ferromagnetism?

•   ↑ ↑ ↑ ↑
•  ↑ ↓ ↑ ↓
•  ↑ ↑ ↑ ↓ ↓
•  None of these

Solution
Ferromagnetism is due to spontaneous alignment of the magnetic dipoles in same direction.

Q4. The unit cell with the structure below refers to……crystal system.

•  Cubic
•  Orthorhombic
•  Tetragonal
•  Trigonal

Solution
Note that a≠b≠c and α=β=γ=90°, the conditions for orthorhombic system.

Q5.The fraction of total volume occupies by the atoms present in a simple cube is :

•  
•  
•  
•  

Solution
 

Q6. In an antifluorite structure, cations occupy

•  Octahedral voids
•  Centre of cube
• Tetrahedral voids
•  Corners of cube

Solution
In antifluorite structure, the anions are oxide ions. The oxide ions form a face centred cubic array and the metal ion (cation) fill half of the tetrahedral voids. e.g., -Na2O.

Q7.The structure of MgO is similar to NaCl. The co-ordination number of Mg is :

•  2
•  6
•  4
•  8

Solution
Na has 6 co-ordination number (fcc structure).

Q8.The phenomenon in which crystals on subjecting to a pressure or mechanical stress produce

electricity is called :

•  Pyro-electricity
•  TPiezo-electric effect
•  Ferro-electricity
•  Ferri-electricity

Solution
It is the definition of piezo-electric effect or piezo-electricity.

Q9.The statement that, “It is possible to choose along the three co-ordinate axes unit distance a, b, c

not necessarily of the same length, such that the ratio of there intercepts of any plane in the crystal is

given by in ma :nb :pc where m,n,p are either integral whole numbers including infinity or fraction of

whole number” is known as :

•  Hauy’s law of rationality of indices
•  The law of constancy of interfacial angles
•  The law of constancy of symmetry
•  None of the above

Solution
This is Hauy’s law of rationality of indices.

Q10. Crystals which are good conductor of electricity and heat are known as :

•  Ionic crystals
•  Covalent crystals
•  Metallic crystals
• Molecular crystal

Solution
Metallic crystals are good conductor of heat and current due to free electrons on them.